The government will allocate customs passes to thousands of businesses over the next two weeks to prevent goods being held up at the UK border in the event of a no-deal Brexit.

The chancellor, Sajid Javid, said giving unique customs numbers to 88,000 exporters was part of the Treasury’s £2.1bn of extra no-deal preparations and would “ease the flow of goods at border points and support businesses to trade and grow”.

Without the customs passes, goods could be impounded at UK ports and airports.

Business lobby groups said it had taken months of discussions with the Treasury to persuade ministers they should allocate numbers rather than wait for businesses to sign up.

Until now, the 250,000 businesses that export to the EU have been encouraged to ask for a customs pass. About 72,000 had signed up by last month.

It is understood that about 90,000 small businesses, mostly sole traders with a turnover below the VAT threshold, have yet to be issued with an Eori (economic operator registration and rdentification) number.

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Adam Marshall, the director general of the British Chambers of Commerce, said: “This step is long overdue. The proportion of firms applying for Eori numbers was concerningly low, and automatic issuance will help ease the administrative burden facing companies in the weeks and months ahead.”

But he criticised ministers for being slow to launch an official database to provide information on tariffs and quotas for a no-deal Brexit.

Even with a customs pass there is no guarantee the EU will recognise Eori numbers after 31 October should a no-deal Brexit go ahead.